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991.
OBJECTIVEBetter preconception metabolic and nutritional health are hypothesized to promote gestational normoglycemia and reduce preterm birth, but evidence supporting improved outcomes with nutritional supplementation starting preconception is limited.RESEARCH DESIGN AND METHODSThis double-blind randomized controlled trial recruited from the community 1,729 U.K., Singapore, and New Zealand women aged 18–38 years planning conception. We investigated whether a nutritional formulation containing myo-inositol, probiotics, and multiple micronutrients (intervention), compared with a standard micronutrient supplement (control), taken preconception and throughout pregnancy could improve pregnancy outcomes. The primary outcome was combined fasting, 1-h, and 2-h postload glycemia (28 weeks gestation oral glucose tolerance test).RESULTSBetween 2015 and 2017, participants were randomized to control (n = 859) or intervention (n = 870); 585 conceived within 1 year and completed the primary outcome (295 intervention, 290 control). In an intention-to-treat analysis adjusting for site, ethnicity, and preconception glycemia with prespecified P < 0.017 for multiplicity, there were no differences in gestational fasting, 1-h, and 2-h glycemia between groups (β [95% CI] loge mmol/L intervention vs. control −0.004 [−0.018 to 0.011], 0.025 [−0.014 to 0.064], 0.040 [0.004–0.077], respectively). Between the intervention and control groups there were no significant differences in gestational diabetes mellitus (24.8% vs. 22.6%, adjusted risk ratio [aRR] 1.22 [0.92–1.62]), birth weight (adjusted β = 0.05 kg [−0.03 to 0.13]), or gestational age at birth (mean 39.3 vs. 39.2 weeks, adjusted β = 0.20 [−0.06 to 0.46]), but there were fewer preterm births (5.8% vs. 9.2%, aRR 0.43 [0.22–0.82]), adjusting for prespecified covariates.CONCLUSIONSSupplementation with myo-inositol, probiotics, and micronutrients preconception and in pregnancy did not lower gestational glycemia but did reduce preterm birth.  相似文献   
992.
Aims Using cross‐sectional national survey data, we assessed young peoples' beliefs about the role of alcohol, tobacco and marijuana in the prevention and treatment of mental disorders as well as the predictors of these beliefs. We also compared these findings with those from a similar survey carried out in 2006. Design, setting and participants Between January and May 2011, a national computer‐assisted telephone survey was conducted on a representative sample of Australian youths aged 15–25 years. A total of 3021 young people were presented with a case vignette portraying depression, depression with suicidal thoughts, psychosis, social phobia, depression with alcohol misuse or post‐traumatic stress disorder in a young person. Measurements Respondents were asked about their beliefs regarding the role of using alcohol, tobacco and marijuana in preventing or dealing with the mental disorders described in the vignettes. Level of psychological distress was assessed by the Kessler 6 scale (K6). Findings More than 75% of respondents agreed that the three substances were harmful for the young people in the vignettes, and that not using marijuana or drinking alcohol in excess is preventive. Males, young adults and more distressed respondents were less likely to endorse these beliefs. No significant changes were observed between surveys. Conclusions Most young people in Australia are aware of the negative impact of substance use on mental disorders, but a few high‐risk groups remain: males, young adults and those with more psychological distress. Future public health campaigns need to target these groups and focus on translating young people's substance use beliefs into behavioural change.  相似文献   
993.

Objective

The goal of this study was to compare the semi-quantitative Goutallier classification for fat infiltration with quantitative fat-fraction derived from a magnetic resonance imaging (MRI) chemical shift-based water/fat separation technique.

Methods

Sixty-two women (age 61?±?6 years), 27 of whom had diabetes, underwent MRI of the calf using a T1-weighted fast spin-echo sequence and a six-echo spoiled gradient-echo sequence at 3 T. Water/fat images and fat fraction maps were reconstructed using the IDEAL algorithm with T2* correction and a multi-peak model for the fat spectrum. Two radiologists scored fat infiltration on the T1-weighted images using the Goutallier classification in six muscle compartments. Spearman correlations between the Goutallier grades and the fat fraction were calculated; in addition, intra-observer and inter-observer agreement were calculated.

Results

A significant correlation between the clinical grading and the fat fraction values was found for all muscle compartments (P?R values ranging from 0.79 to 0.88). Goutallier grades 0–4 had a fat fraction ranging from 3.5 to 19%. Intra-observer and inter-observer agreement values of 0.83 and 0.81 were calculated for the semi-quantitative grading.

Conclusion

Semi-quantitative grading of intramuscular fat and quantitative fat fraction were significantly correlated and both techniques had excellent reproducibility. However, the clinical grading was found to overestimate muscle fat.

Key Points

? Fat infiltration of muscle commonly occurs in many metabolic and neuromuscular diseases. ? Image-based semi-quantitative classifications for assessing fat infiltration are not well validated. ? Quantitative MRI techniques provide an accurate assessment of muscle fat.  相似文献   
994.

BACKGROUND:

Necrotizing enterocolitis (NEC) is the most common gastrointestinal disease in neonatal intensive care units. Although the pathogenesis of NEC remains unclear, evidence suggests that infections, especially bacterial infections, may play an important role. Viral infections may also result in NEC. Several outbreaks of NEC associated with rotaviruses have been described previously.

OBJECTIVE:

To investigate the association between rotavirus (RV) and serum interleukin (IL)-6 and IL-8 levels in infants with NEC.

METHODS:

RV infections were prospectively studied using antigen detection in the stools of 31 infants with NEC. Additionally, serum levels of IL-6, IL-8 and tumour necrosis factor-alpha were tested using micro-ELISA at 0 h and 48 h after diagnosis of NEC.

RESULTS:

Fecal specimens from 13 infants were positive, while fecal specimens from 18 infants were negative for RV according to antigen detection (RV+ and RV− groups, respectively). The mortality rate and the severity of NEC were not significantly different between the RV+ and RV− groups. IL-6 levels at 0 h and 48 h after diagnosis of NEC in RV+ infants were lower compared with RV− infants, while IL-8 levels were greater at 0 h and 48 h after diagnosis of NEC in RV+ infants compared with RV− infants.

CONCLUSION:

A high prevalence of RV infection in neonates with NEC was found. Decreased IL-6 levels and increased IL-8 and tumour necrosis factor-alpha levels in RV+ neonates with NEC suggests a role for RV in NEC.  相似文献   
995.
Growing Up in Singapore Towards healthy Outcomes (GUSTO) is Singapore's largest birth cohort study to date. The main aim of GUSTO is to evaluate the role of developmental factors in the early pathways to metabolic compromise. Detailed data is collected for a range of environmental exposures in the parents and offspring, and allergic disorders are among a number of outcomes assessed in infancy and childhood. Under the Allergy domain of GUSTO, this integrated study will describe the epidemiology of allergic manifestations and different phenotypes in the Asian context and help shed light on the association of metabolic disease to allergy. Epigenetic mechanisms and associations with other childhood disorders will also be explored. The aim of this report is to focus on methodology of GUSTO, and to suggest similar approaches (i.e., integrated cohort studies on pediatric allergy) worldwide. Recruitment commenced in 2009 with a cohort of 1,163 pregnant mothers in their first trimester. The mothers and children were followed throughout pregnancy and follow-up will continue until the child reaches 3 years of age. Preliminary results showed that 39.8% of the mothers had a personal history of having at least one allergic disease, which included asthma, eczema and allergic rhinitis. Further data collection and analyses are still ongoing. Allergy is a complex spectrum of disorders with numerous poorly-understood aspects. The ongoing GUSTO cohort study, with its longitudinal design and multi-disciplinary nature, may provide new insights into developmental influences on allergy. As a Singapore-based study, it will be the first integrated allergy cohort in Southeast Asia, of which recruitment started during pregnancy.  相似文献   
996.
997.
998.
Sustainable and green machining technologies have become a welcomed topic in the manufacturing industries. One of the emerging sustainable technologies is minimum quantity lubrication (MQL). In this study, the optimisation and study of the bubble-bursting atomisation system applied to MQL machining is carried out through the computational fluid dynamics (CFD) simulation approach. Vegetable oil is selected as the cooling lubricant in this study. The performance of the bubble-bursting atomisation system is improved by alternating air inlet velocity and the gap distance between the inlets of bubble production. A velocity of 0.1 ms−1 is suitable for the air at the inlets for the bubble production, whereas 10 ms−1 is suitable for the velocity of the air at the inlet, where the droplets of vegetable oil are guided to the nozzle. Besides that, a 50 mm gap distance between the air inlets for the production of bubbles is able to avoid the occurrence of bubble coalescence. Under these conditions, optimal bubble sizes of 2–3 mm can be achieved, with a higher probability of nano-sized droplets being present in these ranges. Furthermore, a higher rate and smaller size of vegetable oil droplets escaping the atomisation chamber and reaching the machining zone will be generated. Thus, the performance of the MQL machining can be improved.  相似文献   
999.
OBJECTIVE: The detection of flat colorectal lesions with possible malignant potential has been described by Japanese endoscopists. This study looks at the detection of flat lesions using standard colonoscopic techniques and examines the clinical significance of these lesions. METHODS: The records of patients who underwent complete colonoscopy by a single colorectal surgeon in an outpatient setting over a 4-year period were reviewed. The site and number of flat lesions and their histology were noted. Patients with incomplete intubation of the colon were excluded. RESULTS: A total of 491 patients underwent 593 colonoscopic examinations. There were 236 flat lesions identified in 91 patients: 24% (56/236) were adenomas showing mild or moderate dysplasia, and 63% (148/236) were hyperplastic. CONCLUSIONS: Flat colorectal lesions are common and can be detected without the aid of dye spray and magnification. One-quarter of these lesions are adenomatous and we recommend routine hot biopsy or polypectomy of these lesions.  相似文献   
1000.
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